1. Technical Field
The present teaching relates generally to methods and systems for communications. More specifically, the present teaching relates to methods and systems for communicating multiple data signals and systems incorporating the same.
2. Discussion of Technical Background
In modern communications, data signals that are to be communicated frequently have to be sampled and such sampled data signals are then transmitted. Particularly, when there are multiple data signal inputs, to transmit such multiple data signals, a conventional approach is to employ multiple isolation components to isolate each data signal prior to transmitting each data signal. Isolated communications are commonly implemented based on passive components, active (e.g., opto-couplers), or passive-active (GMR) in which galvanic isolation can be supported.
Traditionally, communication protocols for such physical implementations falls within two categories. In one category, multiple signals are serialized so that multiple signals can be communicated over a single isolation component. In this category, a single fixed clock is used for both sampling and transmission at a fixed refresh rate. One example circuit of this category is provided in FIG. 1 (PRIOR ART). With such a circuit, signal processing and sampling create systematic jitter and therefore it is not desirable.
Another category of prior solutions is to have each signal transmitted over a separate isolation component. With such solutions, to transmit multiple data signals, multiple isolation components have to be deployed. Multiple isolation components increase both the physical area needed and the isolation barrier capacitance. A typical circuit of this type of solution is illustrated in FIG. 2 (PRIOR ART). With this prior art solution, the clock used is event driven. An event can be when an edge of an input signal is detected. Such an event will activate an event driven timer, as shown in FIG. 2, and the activated clock will be used to sample and transmit data signals.
One problem with this solution is that, even when a single signal is to be transmitted, transmitting a refresh signal causes jitter when a single isolation component is used so that an additional isolation component is needed for transmitting the refresh signal, leading to the same problem of the increased physical space as well as isolation barrier capacitance.